public async Task <IEnumerable <GeoClusterLocation> > GetGeoLocationClustersAsync(
GetGeoLocationClustersRequest request,
CancellationToken cancellationToken)
{
IEnumerable <MediaGeoLocation> medias = await _mediaStore.FindMediaInGeoBoxAsync(
request.Box,
100000,
cancellationToken);
var clusters = new List <GeoClusterLocation>();
if (medias.Count() < 500 && request.Precision > 10)
{
//Add every item as cluster
foreach (MediaGeoLocation media in medias)
{
clusters.Add(new GeoClusterLocation()
{
Hash = GeoHash.Encode(
media.Coordinates.Latitude,
media.Coordinates.Longitude),
Coordinates = media.Coordinates,
Id = media.Id,
Count = 1
});
}
}
else
{
medias.ToList().ForEach(x => x.GeoHash = x.GeoHash.Substring(0, request.Precision));
IEnumerable <IGrouping <string, MediaGeoLocation> > grouped = medias
.GroupBy(x => x.GeoHash);
foreach (IGrouping <string, MediaGeoLocation>?group in grouped)
{
GeohashDecodeResult decoded = GeoHash.Decode(group.Key);
var cluster = new GeoClusterLocation
{
Hash = group.Key,
Count = group.Count(),
Coordinates = new GeoCoordinate
{
Latitude = decoded.Coordinates.Lat,
Longitude = decoded.Coordinates.Lon
}
};
if (group.Count() == 1)
{
cluster.Id = group.First().Id;
}
clusters.Add(cluster);
}
}
return(clusters);
}